There are two types of signal transmission cables; what is called the one using an electrical signal, and the one using an optical signal.
The one using the electrical signal is easy to handle and a general purpose-type, however, has defect in having limitation in high speed transmission and is weak against an electromagnetic interference. The optical signal has advantage of being capable of transmitting in high speed and also not receiving the electromagnetic interference. As a medium for transmitting the optical signal, an optical fiber is used, however, it is generally rigid and inferior in handling. Accordingly, it is used in many cases as a fixed wiring. As the one which has improved this drawback, there is an optical fiber curl cord (hereinafter, see PATENT DOCUMENT 1).
However, the curl cord has a problem of large outer diameter, easy catching of a curled part, and easy hanging when it is held horizontally, and is not an article with sufficiently enhanced handling.
On the other hand, in recent years, development of a robot or a wearable electronic device is significant, and such a case has been increasing that requires to instantaneously communicate (that is, high speed signal transmission) an image (moving image) obtained using a camera with a calculator (computer). In particular, in the wearable electronic device, since the optical fiber is rigid and does not deform with following the actions, there has been a problem that it cannot provide a wiring which fits to a body and thus has poor wearing feeling.
To solve such a problem, such an optical fiber cable has been required that has compliance with shape deformation, and is not caught or entangled in deforming, and can transmit an optical signal even in a deformed state, and has straight shape which can be used in repetitive extension and has extensity.